Steel rule lined blank and pierce die and method of making same



Jan. 26, 1965 R. M. KROUSKOP 3,166,968

STEEL RULE LINED BLANK AND PIERCE DIE AND METHOD OF MAKING SAME Filed Sept. 1, 1961 4 Sheets-Sheet 1 2 25 7 Z6 /j/ 35 I 35 36 27 20 5% w 040 Z2 Z4 /0 5 1 35 i 3 3.9 23 /9 J4 INVENTOR FIGURE 3 BY Jan. 26, 1965 R. M. KRousKoP 3,166,968

STEEL RULE LINED BLANK AND PIERCE DIE AND METHOD OF MAKING SAME Filed Sept. 1, 1961 4 Sheets-Sheet 2 FIGURE 4 FIGURE 5 INVENTOR R/CHAAD M K/POUJ/(OP ATTORNEY Jan. 26, 1965 M. KROUSKOP 3,166,968

STEEL RULE LINED BLANK AND PIERCE DIE AND METHOD OF MAKING SAME Filed Sept. 1, 1961 4 Sheets-Sheet 3 III ml /0 I va a; A445 m 50 q 'hf AME/7 M2 /22 M f /Zd5 /42 U7 #0 1 HI INVENTOR R/CH%AD M K/QUUS/(Q A'ITORNEY Jan. 26, 1965 R. M. KROUSKOP 3,165,968

STEEL RULE LINED BLANK AND PIERCE DIE AND METHOD OF MAKING SAME Filed Sept. 1, 1961 4 Sheets-Sheet 4 FIGURE 9 INVENTOIR fP/CHAHQ M. KROUSKOP 19/ I l ATTORNEY Patented Jan. 26,- 1-965 United rates Patent Gfifice 1166968 3,166,968 STEEL RULE LINED BLANK AND PIERCE DIE AND METHOD OF MAKING SAME Richard M. Krouskop, Grand Rapids, Mich, assignor, by

mesne assignments, to Kro-Die, Inc., Grand Rapids,

Mich., a corporation of Michigan Filed Sept. 1, 1961, Ser. No. 135,519 11 Claims. (Cl. 83-681) This invention relates to a die structure and more particularly to steel rule blank and pierce die units as are used for blanking and piercing various configurations from sheet material.

The art of making and using punch and die units, including blanking and piercing die units, is an old art. This is the art to which the present invention pertains, particularly the art of making such matched punch and die units or blank and piercing die units. In the past, many methods of making such punch and die units, including the individual punch unit and the individual die unit thereof, have been proposed, but few have been placed in general practice. Great advances have been made since the time when both male or punch member and female or die member were individually machined from suitable pieces of steel die stock and properly hardened for use in a press, and perhaps the foremost develompent to date in the art of making such tools is exemplified by the procedure of US. Patent 2,495,221, issued January 24, 1950. However, even in this advanced development in the art of producing punch and die units, the formed female die unit is clamped in the ram of a suitable punch press and adjusted so that, on a downstroke ofthe ram, the sharp edges of the cutting rule of the female die unit will be pressed into the plate of suitable die stock to mark off the exact outline of the inner periphery of the female die unit on the surface thereof. The die stock is at this point removed from the press and suitably machined, to provide an outer periphery which corresponds to the outer periphery of the part to be produced and the inner periphery of the female die unit, by following the outline cut into it by the sharp edges of the cutting rule of the female die unit. Thus, although the construction of such tools is facilitated by the process of the said patent, it nevertheless leaves much to be desired. Still less complicated procedures which completely obviate the machining of steel die stock, which is extremely expensive and time-consuming, and improved and simplified methods for the production of such matching punch and die units, have long been sought.

It has now been found that such matching punch and die units, especially blank and pierce die units, can be made in a simple, facile and economical manner which completely obviates all of the disadvantages of the prior art.

An object of the present invention is to provide a new and improved die set.

Another object of the invention is to provide a simple, inexpensive blank and pierce die set made from steel rule and cast material.

Still another object of the invention isto provide a blank and pierce die having long life while being light in weight.

A further object of the invention is to provide a blank and pierce die having a resistance to warpage due to storage, moisture in surrounding area thereof, or to continuous usage.

A still further object of the invention is to provide a novel blank and pierce die and a method of making the same whereby a punch member or insert is integrally secured to the steel rule with cast material.

Further objects and advantages of the present invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the present invention, reference may be had to the accompanying drawings in which:

FIGURE 1 is a top plan view of a punch unit of the present invention with pierce members in place prior to pouring of the cast matrix.

FIGURE 2 is a top plan view of the punch unit of FIGURE 1 with pierce members in place and with template superimposed thereover with a portion broken away showing the steel rule prior to pouring of the cast matrix.

FIGURE 3 is a vertical section taken along line III III of FIGURE 2 of the punch unit in a frame after pouring of the cast matrix into the space enclosed by the steel rule, showing the cast matrix poured in place and showing complementary punch members inserted into the pierce members.

FIGURE 4 is a top plan view of a punch unit according to the present invention, with pierce members in place, after pouring and solidification of the cast matrix.

FIGURE 5 is a top plan view of a die unit according to the present invention, showing punch members in place, prior to pouring of the cast matrix.

FIGURE 6 is a top plan view of the punch unit of FIGURE 4 inserted in the die unit with punch members of the die unit matching with the pierce members of the punch unit, before pouring of the cast matrix in the die unit.

FIGURE 7 is a vertical section taken along line VII-VII of FIGURE 6, showing the matching punch and die units in a frame after pouring of the cast matrix in the die unit.

FIGURE 8 is an isometric view of the completed die unit showing punch members thereof located in the inner area of the die unit.

FIGURE 9 is an isometric view of the completed punch unit showing cast matrix inside and outside of the steel rule.

General Description die unit by forming another steel rule around the punch a unit. The steel rule of the die unit is hardened, welded and provided with suitable ties and then placed in a frame on a supporting block. The completed punch unit is partially inserted into the steel rule of the die unit and cast matrix is poured inside and outside of the steel rule and allowed to solidify. Whenever it is necessary to provide an extremely durable punch unit, the punch unitis placed in a frame on a supporting block and cast matrix is poured outside of the steel rule and allowed to solidify. If desired, pierce members can be inserted into the punch unit and matching punch members can be inserted into the die unit prior to the pouring of the cast matrix. The completed punch and die units are then mounted in a punch press and employed in the usual manner for blanking and piercing sheet material partsj Specific Description.

Reference is now made to the accompanying drawings for a better understanding of the invention, in which all the parts are numbered and in which the same numbers are used to refer to corresponding parts throughout.

In the punch unit 113 shown in FIGURE 1 there is pro vided a steel blanking rule 11 bent to conform to the perimeter of a blank or part which is to be produced from sheet material such as sheet steel, plastic or any other ferrous or nonfer'rous material. An outer preiphery 13 of the steel rule 11 defines the perimeter of the blank produced. After the steel rule is formed to a specific configuration, it is hardened by one of various methods well known in the art. Whether the steel rule '11 is made from one piece 11 or a plurality of pieces 11 and 12 depends to a certain extent on the size as well as the complexity of the irregular perimeter of the blank. The ends of the hardened steel rule 11 or 11 :and '12 are then secured together by a weld 14 at their juncture 15.

Various means can be employed for mechanically securing-or tying the steel rule into a cast material or matrix. For instance, an opening 16 can be provided in the wall of the steel blanking rule 11 of the punch unit to provide one means for tying the steel rule into the 03151; matrix upon pouring of the latter. A'piece of adhesive tape 27 or other suitable material is placed over the outside of opening 16 to restrict the-flow of cast matrix 37 (not shown in FIGURE 1). Bolts '17 can be inserted through openings in the wall of'the steel rule andsecured by nuts 18 on theinside wall of'the'steel rule to provide other means for tying the steel rule into the cast matrix upon pouringof the latter. Bolts or pins 19 can be secured by weld' 20 to the inside wall of the steel rule to provide a further tie of the steel rule to the cast matrix upon pouring'of the latter. 'Apie'rce member 21 made from steel and hardened is disposed inside the confines of the steel rule of punch unit 10 having an opening 22 defining an area B desired inth'e'blank to be'pro'duced. Another 'pierce member 23 also made from steel and hardened is disposed inside'the confines'of the steel rule of punch unit 10 having an opening 24 defining the area C having the dimensions of an opening desired in the blank to be produced.

As shown in FIGURE 2 the steel rule 11 constitutes the perimeter of the punch unit 10 with its cuttiiQg edge or outer periphery 13 having a template 25 corresponding to the blank to be produced superimposed thereupon. Opening 22a defining area B and opening 24a defining area C having the respective dimensions of openings desired in the part to be produced are also shown in the template 25. In addition, a further opening or pouring orifice 26 is provided in the template 25 through which orifice cast matrix can be poured into the interior of the steel rule 11. In the preferred form of the invention the casting ma terial or matrix can comprise a strong plastic material mixed with metallic pieces or powders. The percentage of metal in the plastic material depends upon the uses to which the punch and die units are to be subjected. Various compositions of plastic material and metallic powders are readily available on the market in a semi-viscous liquid state and can be employed in makingpunch and die units. It must be understood, however, that it is not necessary to use any of the compositions available on the market and that the casting matrix can comprise one or more various thermosetting plastic materials having high tensile and. compressive strength with or without suitable metallic pieces or powders, or even metal or other suitable chips or blocks which may be used to reduce the amount of casting material employed.

- Punch unit 10 is then placed on a supporting block 34 (FIGURE 3). The steel blanking rule'll defining the outer edges of the punch unit 11 is mounted on the block or platform 34 which pierce members 21 and 23 disposed within the confines of the steel rule. The pierce members 21 and 23 are recessed at 38 and 39, respectively, so as to form a locking mechanical bond with cast matrix 37.

A layer or thickness of release material 35 is disposed on the portion of block 34 and template 25 coming in contact with the cast matrix to prevent the block and template from adhering thereto.- Bolt 19 welded by Weld 21) to the inner wall of the steel rule 11, bolts 17 secured by nuts 13 to the steel rule 11 and the opening 16 in the wall of steel rule 11provide means for tying the steel rule into the cast matrix.

The punch unit 10, including pierce members 21 and 23, template 25 and block 34, is rigidly secured in a frame indicated by clamps 36. For the purpose of aligning the pierce members 21 and 23 in punch unit 10, the punch members 128 and 132 used in the complementary die unit 1113 are inserted through openings 22a and 24a in template 25 and into openings 22 and'24 of pierce members 21 and 23 respectively of punch unit 10. As shown, punch member 128 has a beveled edge vat 129, a pointed nose at 130 and a main portion 127 having a dimension corresponding to opening 22. Punch member 132 has a dimension greater than that of opening 24 at its base in which is provided a recess 133 but has a main portion 131 having a dimension corresponding to opening 24. Of course, there is a small tolerance between the main portion 127 of punch member 128 and opening 22 of pierce member 21 and between the main portion 131 of punch member 132 and opening 24 of pierce member23 to permit proper Working thereof. Beveled edge-129 of punch member 128 and recess 133 of punch member 132 are provided for mechanically bonding and tying with the cast matrix of the complementary die unit as will become apparent hereinafter.

FIGURE 4 shows the partially completed punch unit 10 with outer boundary of steel blanking rule 11 having an outer periphery 13 defining the outline of the blank or part having area A desired to be produced. Interior of the punch unit 10 is cast matrix 37, and integrally interbonded by the cast matrix 37 to the steel blanking rule are pierce'mem'bers 21 and 23 made from steel and hardened with their respective openings 22 and 24, respectively defining areas B and C having dimensions corresponding to openings desired in the part to be pro duced.

In the die unit shown in FIGURE 5 there is provided a steel blanking rule 111 formed about the outer periphery of the punch unit 10 of FIGURE 4. The inner periphery 113 of the steel blanking rule 111 corresponds to the outer periphery 13 of the blanking rule 11 of the punch unit of FIGURE 4, in turn conforming to the outer periphery of the part to be produced. Here also the steel rule can be made fromone piece or a plurality of pieces depending to a certain extent on the size as well as the complexity of the irregular perimeter of the blank or part to be produced. The steel rule 111 is then hardened by one of various methods well known in the art after'it is formed to a specific configuration.

119 are secured to the wall of the steel blanking rule 111 by welds 120, while an opening 11s is provided in the wall the punch and die units are secured by clamps 136.

of the steel blanking rule 111, all to provide various means for tying with the cast matrix to be cast about the interior and exterior of the steel blanking rule 111. A strip of adhesive tape 124 is placed over the opening 116 to restrict the flow of cast matrix. Located within the confines of steel rule 111 are punch members 128 and 132 having respective dimensions as at 127 and 131 corresponding to the dimensions of openings desired in the part to be produced, the openings being respectively identified as having areas B and C. Pointed nose 131} and beveled edge 129, both non-essential elements, of punch member 128 are also visible in FIGURE 5.

As depicted in FIGURE 6 and FIGURE 7, die unit 110 is then placed on top of a supporting block or platform 1341 and enclosed by a frame 14%. Punch unit 11, with its outer edge of steel blanking rule 11 is partially inserted within the confines of steel blanking rule 111 of die unit 110. The inner periphery 113 of steel rule 111 of die unit 111) as well as the outer periphery 13 of steel rule 11 of punch unit 119 define the outer configuration A of the part to be produced. Opening 26 is provided in the cast matrix 3'7 of punch unit 18 for pouring of cast matrix through opening 126 and into die unit 110 within the confines of steel rule 111. Opening 126 may be filled in after die unit 1119 has been cast. The pierce members 21 and 23 of punch unit 111 with their respective openings 22 and 24 as well as corresponding main portions 127 and 131 respectively of punch members of die unit 111) corresponding to said openings 22 and 24 of said pierce members 21 and 23 of said punch unit are shown in proper alignment.

FIGURE 7 shows a vertical section of the elements shown in FIGURE 6 enclosed in the frame 1 11i mounted on block 134 rigidly secured by clamps 136. Suitable gauge blocks 142, risers 141 above the frame 149, and suitable spanners 143 are employed for positioning and securing the punch unit 11 and the die unit 1113 to the supporting block 134. A suitable layer or thickness of release material as indicated at 155 is disposed on the inside wall of frame 141i and on block 134- to prevent the like shearing edge. Punch members 128 and 132 by virtue of beveled edge 129 and recessed base 133 are securely interbonded to and mechanically tied in with cast matrix 138 Within the confines of steel rule 111 of die unit 1111 and the respective main portions 127 and 131 thereof defining openings desired in the part to be produced extend upwardly and partially into openings 22 and 24 for alignment with the punch members 128 and 132 made from steel and hardened in die unit 1111. Cast matrix 137 can be poured into a cavity formed by the outer periphery of steel blanking rule 111, the frame 14-6, and a portion of the supporting block 134 before or after A metered amount of cast matrix 138 is poured through .opening 126 into a cavity confined by the the steel rule 111 and hte supporting block 134- for mechanically tying the punch members to the steel rule 111, otherwise an inadequate air space 144 between the punch unit 111 and die unit 110 may prevent the mounting of a not shown stripper pad for facilitating the removal of the part produced during the blank and pierce operation.

FIGURE 8 shows a completed die unit 11h with cast matrix 137 exterior of steel rule 111 and cast matrix 138 interior of the steel blanking rule. The inner periphery 113 of steel rule 111 of die unit 1111 defines the dimensions of an area A of the part to be produced. Punch memher 128 of the die unit having its main portion 127 defining an area of an opening B desired in the part to be produced as well as punch member 132 of die unit 110 having its main portion 131 defining an area C having the dimensions of an opening desired in the part to be produced are also apparent.

Whenever it is necessary to make an extremely durable punch unit, the punch unit 10 as shown in FIGURE 4 is placed in a frame and supported on a. block or platform and a metered amount of cast matrix 33 is poured into the space bounded by the frame, the outside periphery 13 of the steel rule 11, and a portion of the block. Various means such as pins or bolts can be secure to the outside of the steel rule 11 for mechanically tying the steel rule to the cast matrix. The completed punch unit, after being removed from the frame and block, is shown in FIGURE 9. The cast matrix 33 provided on the outside of the steel rule 11 also retards the growing of the steel rule resulting from long continuous use of the punch unit 10.

Operation in operation, the completed punch unit 10 and the die unit 1111 are mounted on the opposed faces of a press in proper alignment and operated in a manner well known in the art for any blank and pierce matching punch and die unit. Part strippers and/or stripper pads used in the art are at this time mounted on the die and punch units as well as gauge pins, guides and other standard operating devices.

In preparation of the respective punch and die units, one or more pieces of steel blanking rule 11 in FIGURE 1 are provided and formed so as to have a configuration exactly corresponding to the outer periphery of a part to be produced. The steel blanking rule after it is formed to a specific configuration is hardened by one of various methods well known in the art. The section or sections of steel blanking rule are securely joined together as by welding at their juncture or junctures, as at 14 and 15 in FIGURE 1. Various ties can be secured to the walls of the steel blanking rule. A bolt 19 can be welded to the rule or the rule can be provided with countersunk type openings in the wall of the steel blanking rulefor inserting bolts 17 therein secured by nuts 18 facing the inner confines of the steel rule 11. Other openings such as 16 having a piece of adhesive tape 27 placed on the outside wall in FIGURE 1 may be provided in the wall of the steel rule 11 so as to allow further mechanical ties with the cast matrix and the steel rule itself by virtue of the cast matrix entering such openings. Any pierce members, located internally of the confines of the steel rule and in the approximate positions where they should be located in respect to the complementary punch members of the die unit of the matching die set, have openings such as at 22 and at 24 respectively of pierce members 21 and 23 which correspond to openings desired in the part or blank to be produced.

A template having the exact configuration of the part to be produced is then placed over the steel rule 11 defining the outer periphery of the punch unit and the template in addition to openings 22a and 24a is provided with an opening such as at 26 in FIGURE 2 for purposes of allowing pouring of the cast matrix into the inner confines of the steel rule of the punch unit. The steel rule, pierce members and template comprising an assembly, are then placed on a supporting block 34. Prior to pouring of the casting material into the inner confines of the steel rule of the punch unit, however, the superimposed template and the block are provided with a layer or thickness of release material thereon. The entire assembly is then secured together by clamps, after the punch members of the complementary die unit are inserted through the template and into the openings of the pierce members of the punch unit so as to provide proper alignment between the punch members and the openings in the pierce members of the punch unit. Pouring of the cast matrix is then completed while the punch members are in place in the openings of the pierce mem-. bers, the cast material is allowed to solidify, and the completed punch unit is then removed from the clamps, at which time it has the configuration and appearance substantially as shown in FIGURE 4.

The complementary die unit 110 is then produced by forming one or more pieces of steel rule exactly around the outer periphery of the punch unit lltl. After the steel rule has been formed it is hardened by means well known in the art. The juncture or junctures thereof are secured to each other as by welding, as at 114 and 115 in FIGURE 5. Suitable ties can be provided in the wall of the steel rule, as at 117 and 118, 119 and 120, or 116 in FIGURE with adhesive tape 12d over the opening 116. In the preferred form of the invention, the steel rule for the punch or die units is hardened after it is formed to a specific configuration; however, the steel rule can be hardened after it is secured together by welding or other suitable means and provided with suitable ties. The punch members of the die unit are then located in their approximate positions internally of the steel rule of the die unit being produced, as at 128 and 132. in FIGURE 5.

The die unit assembly comprising the steel rule and the punch members is then placed on block 134 enclosed by'frame 149 having suitable release material lining the sides of the frame Mt) and the block upon which it is located. Pouring of the cast matrix 137 in'the cavity enclosed by the steel rule 111 and the inner periphery of the frame 140 then can be performed in any suitable manner to provide an integral inter-bonding therebetween. The punch unit 19 is then inserted partially within the confines of steel rule 111 of die unit 11%), supported in substantial parallel relation to the surface of the block on which the die unit 110 is located as by gauge blocks 142 in FIGURE 7, so as to bring openings 22 and 24 ofthe pierce members of the punch unit into proper alignment with the punch members 128 and 132 of die unit 110 having main portions 127 and 131 exactly corresponding to the openings 22 and 24. Pouring of the cast matrix in the interior of the steel blanking rule 111 of die unit 110 is elfected by providing an opening in cast matrix 37 of punch unit 10, as at 126 in FIGURE 6, through which cast matrix may be poured into the interior of the steel blanking rule 111 of die unit 110. After removal of the punch unit 10 from die unit 110, this opening 126 may be filled in with matrix. The entire assembly is then securely mounted with clamps, suitable risers and spanners, whereupon cast matrix 133 is poured through opening 126 in punch unit 10 into the interior of die unit 110, that is, within the confines of steel rule 111 of die unit 110, thereby to interbond securely steel blanking rule 111 of the die unit 110 with punch members 128 and 132. In the preferred form of the invention, the pouring of the cast matrix 137 is delayed until the entire assembly is securely mounted with clamps. Also, the melting point of the cast matrix in the punch and die units is below the annealing temperature of the steel rules and pierce and punch members.

The clamps are then loosened and the completed punch and die units are separated and removed from the frame and supporting block. The portions of the gauge blocks extending above the cast matrix 138 can be removed by machining or the like after which die unit 110 has 7 the appearance as shown isometrically in FIGURE 8.

Although the punch unit can now be used with the dierunit for blanking and piercing sheet metal material, the punch unit can be reinforced for rugged operation by providing cast matrix exterior of the steel rule 11 to a height of approximately one-half of the height of the rule so as to provide space for a stripper pad (not 'shown). Various ties such as pins or bolts may be, but

are not necessarily, secured to the outside of the steel '8 rule 11 for interbonding the steel rule to the cast matrix. The punch unit then has the appearance as shown isometrically in FIGURE 9. 1

The finished punch unit It) and die unit 119 may then be mounted on the opposing faces of a punch press and employed in the usual manner for blanking and piercing various configurations from sheet material. Part strippers and/or stripper pads used in the art are at this time mounted on the die and punch units as well as gauge pins, guides and other standard operating devices.

It is to be understood that the punch unit and die unit? are sometimes collectively referred to herein as a die set. When so used, the word set is to be distinguished from the tool commonly used to secure dies in a punch press.

It is thus seen that a novel apparatus and method for making such apparatus is here provided, economically and in an easy manner for employment in blanking and piercing parts from sheet material.

It is to be understood that the invention is not to be limited to the exact device or method shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

I claim:

1. A matching punch and die set comprising a punch unit, the outer periphery of which is defined by at least one piece of steel blanking rule, the ends of which are secured to each other to provide a continuous cutting edge for said punch unit, the outer periphery of said punch unit defining the outer periphery of the part to be produced, a pierced member located within the confines of said steel blanking rule and having an opening therein of an area corresponding to the area of an opening desired in the part to be produced, a cast material disposed outside and Within the entire area bounded by the confines of said steel rule integrally bonding the several reaches of the periphery of said steel rule to each other and to said pierce member located within the confines of said steel rule and within said rule being of a depth generally corresponding to the height of said steel rule, and tying means in said rule for bonding said cast material to said rule, a dieunit comprising at least one piece of steel blanking rule, the ends of which are secured to each other to provide a continuous cutting edge for said die unit, the inner periphery of said steel rule of said die unit corresponding to the outer periphery of said punch unit and to the outer periphery of the part to be produced, cast material surrounding the outer periphery of said steel rule of said die unit and being integrally bonded to the outer periphery of said steel rule and of a depth generally corresponding to the height of said steel rule, tying means in said rule for bonding said cast material to said rule, a punch member located within the confines of said steel rule of said die unit and having outer dimensions corresponding to the area of an opening desired in the part to be produced and also corresponding to the area of the opening in the pierce member of said punch unit, and being located within the confines of said steel rule so as to be in complementary relation to the opening of said pierce member of said punch unit when said punch unit is positioned within the confines of said steel rule of said die unit, and the cast material within the entire area bounded by the confines of said steel rule of said die unit integrally bonding the several reaches of the inner periphery of v 9 y a said die unit in operation of the punch and die units as the complementary parts of a matched die set.

2. A matched punch and die set comprising a punch unit and a die unit for punching a blank from sheet material, a steel blanking rule defining the outer perimeter of said punch unit, cast material disposed within the entire area inside of and also outside of said steel blanking rule, and tying means in said rule for mechanically bonding said cast material to said steel blanking rule, a second steel blanking rule defining the inner perimeter of said die unit, cast material disposed within the entire area inside of and also outside of said second steel blanking rule, and tying means in said rule for mechanically bonding said cast material to said blanking rule, the outer perimeter of said punch unit corresponding to the inner perimeter of said die unit for punching said blank from sheet material by a shearing operation.

3. A punch unit essentially of steel rule and cast material for blanking out a part from sheet material comprising a steel blanking rule having its ends secured to each other to provide a continuous cutting edge corresponding to the contour of the part to be blanked, tying means in said rule for improving the bond between said rule and said cast material, and a solidified cast material disposed within the confines of said rule, filling the entire area bounded by said rule, and integrally bonding the several reaches of the inner periphery of said rule to each other and of a depth substantially corresponding to the height of said rule, and additional solidified cast material disposed in a further substantial area around the outside of said rule to a depth less than the height of said rule.

4. The punch unit of claim 3, wherein a pierce member is disposed Within the confines of said rule and integrally bonded thereto by said cast material.

5. A die unit essentially of steel rule and cast material suitable for use with a complementary punch unit for blanking out a part from sheet material comprising a steel blanking rule having its ends secured to each other to provide a continuous cutting edge corresponding to the contour of the part to be blanked, tying means in said rule for improving the bond between said rule and said cast material, and a solidified cast material disposed within the confines of said rule and filling the entire area bounded by said rule and in a further substantial area around the outside of said rule, the depth of said material Within said rule being less than the height of said rule, the depth of said material outside of said rule generally corresponding to the height of said rule.

6. The die unit of claim 5, wherein a punch member is disposed within the confines of said rule and integrally bonded thereto by said cast material.

7. A method of making a die unit suitable for use with a complementary punch unit for blanking out a part from sheet material comprising the steps of forming a steel blanking rule for the die unit having a continuous cutting edge corresponding to the contour of the part to be blanked, providing tying means in said rule, inserting the complementary punch unit at least partially into said rule, disposing a casting material into an area around the outside of said rule to a depth generally corresponding to the height of said rule throughout all reaches thereof to provide a substantial area of cast material outside of said rule, and disposing additional casting material into the space enclosed by said rule to a depth less than the height of said rule throughout the entire area bounded by said rule, and allowing the cast material to solidify both inside and outside of said rule, thereby to produce the die unit.

8. A method of making a punch unit suitable for use with a complementary die unit for blanking out a part from sheet material comprising the steps of forming a steel blanking rule for the punch unit having a continuous cutting edge corresponding to the contour of l9 a the part to be blanked, inserting a pierce member within the confines of said rule, detachably securing a template provided with openings over said rule, inserting a punch member through one of the openings in said template and at least partially into said pierce member, and disposing a casting material through another opening in said template into the space enclosed by said rule to fill the entire area bounded by said rule and into a further area outside of said rule to provide a substantial area of cast material outside of said rule, the depth of the material inside of said rule substantially corresponding to the height of said rule throughout all reaches thereof, the depth of the material outside of said rule being less than the height of said rule throughout all reaches thereof,

and effecting solidification of the cast material both inside and outside of said rule to produce the punch unit.

9. A method of making a die unit suitable for use with a complementary punch unit for blanking out a part from sheet material comprising the steps of forming a steel blanking rule for the die unit having a continuous cutting edge corresponding to the contour of the part to be blanked, inserting a punch of cast material and steel rule member within the confines of said rule, detachably securing the complementary punch unit at least partially in said rule for aligning the inserted punch member with a pierce member in said complementary punch unit, and disposing a casting material into the space enclosed by said rule through an opening in the cast material of said punch unit to fill the entire area bounded by said rule and into a further area outside of said rule to provide a substantial area of cast material outside of said rule, the depth of the material inside of said rule being less than the height of said rule throughout all reaches thereof, the depth of the material outside of said rule generally corresponding to the height of said rule throughout all reaches thereof, and effecting solidification of the cast material both inside and outside of said rule to produce the die unit, and filling said opening in said cast material of said punch unit with additional cast material and eifecting solidification thereof.

10. A method of making a punch unit suitable for use with a complementary die unit for blanking out a part from sheet material comprising the steps of forming a steel blanking rule for the punch unit having a continuous cutting edge corresponding to the contour of the part to be blanked, disposing a casting material into the space enclosed by said rule to a depth substantially corresponding to the height of said rule and throughout the entire area bounded by said rule, and allowing the material to solidify inside of said rule, disposing additional casting material into a further substantial area outside of said rule to a depth less than the height of said rule, and allowing the material to solidify outside of said rule, thereby to produce the punch unit, including the steps of inserting a pierce member within the confines of said rule, detachably securing a template provided with openings over said rule, and inserting a punch member through one of the openings in said template and at least partially into said pierce member prior to pouring of the casting material through another opening in said template into the space enclosed by said rule.

11. A method of making a die unit suitable for use with a complementary punch unit for blanking out a part from sheet material comprising the steps of forming a steel blanking rule for the die unit having a continuous cutting edge corresponding to the contour of the part to be blanked, disposing a casting material into the space enclosed by said rule throughout the entire area defined by said rule and into a further substantial area outside of said rule, the depth of the material inside of said rule being less than the height of said rule, the depth of the material outside of said rule generally corresponding to the height of said rule, and effecting solidification of the cast material both inside and outside of said rule to produce the die unit, including the steps of inserting a punch member within the confines of said rule, and

detachably securing the complementary punch unit at References Cited by the Examiner UNITED STATES PATENTS 7/43 Liskiewicz 83-656 10 9/58 Hempei 83-685 Deubel 3 83-656 Lescallette 83-107 Smith 83-698 X Berlin et a1 83-685 X FOREIGN PATENTS France.

ANDREW R. JUHASZ, Primary Exc zminer.

CARL W. TOMLIN, Examiner. 

1. A MATCHING PUNCH AND DIE SET COMPRISING A PUNCH UNIT, THE OUTER PERIPHERY OF WHICH IS DEFINED BY AT LEAST ONE PIECE OF STEEL BLANKING RULE, THE ENDS OF WHICH ARE SECURED TO EACH OTHER TO PROVIDE A CONTINUOUS CUTTING EDGE FOR SAID PUNCH UNIT, THE OUTER PERIPHERY OF SAID PUNCH UNIT DEFINING THE OUTER PERIPHERY OF THE PART TO BE PRODUCED, A PIERCED MEMBER LOCATED WITHIN THE CONFINES OF SAID STEEL BLANKING RULE AND HAVING AN OPENING THEREIN OF AN AREA CORRESPONDING TO THE AREA OF AN OPENING DESIRED IN THE PART TO BE PRODUCED, A CAST MATERIAL DISPOSED OUTSIDE AND WITHIN THE ENTIRE AREA BOUNDED BY THE CONFINES OF SAID STEEL RULE INTEGRALLY BONDING THE SEVERAL REACHES OF THE PERIPHERY OF SAID STEEL RULE TO EACH OTHER AND TO SAID PIERCE MEMBER LOCATED WITHIN THE CONFINES OF SAID STEEL RULE AND WITHIN SAID RULE BEING OF A DEPTH GENERALLY CORRESPONDING TO THE HEIGHT OF SAID STEEL RULE, AND TYING MEANS IN SAID RULE FOR BONDING SAID CAST MATERIAL TO SAID RULE, A DIE UNIT COMPRISING AT LEAST ONE PIECE OF STEEL BLANKING RULE, THE ENDS OF WHICH ARE SECURED TO EACH OTHER TO PROVIDE A CONTINUOUS CUTTING EDGE FOR SAID DIE UNIT, THE INNER PERIPHERY OF SAID STEEL RULE OF SAID DIE UNIT CORRESPONDING TO THE OUTER PERIPHERY OF SAID PUNCH UNIT AND TO THE OUTER PERIPHERY OF THE PART TO BE PRODUCED, CAST MATERIAL SURROUNDING THE OUTER PERIPHERY OF SAID STEEL RULE OF SAID DIE UNIT AND BEING INTEGRALLY BONDED TO THE OUTER PERIPHERY OF SAID STEEL RULE AND OF A DEPTH GENERALLY CORRESPONDING TO THE HEIGHT OF SAID STEEL RULE, TYING MEANS IN SAID RULE FOR BONDING SAID CAST MATERIAL TO SAID RULE, A PUNCH MEMBER LOCATED WITHIN THE CONFINES OF SAID STEEL RULE OF SAID DIE UNIT AND HAVING OUTER DIMENSIONS CORRESPONDING TO THE AREA OF AN OPENING DESIRED IN THE PART TO BE PRODUCED AND ALSO CORRESPONDING TO THE AREA OF THE OPENING IN THE PIERCE MEMBER OF SAID PUNCH UNIT, AND BEING LOCATED WITHIN THE CONFINES OF SAID STEEL RULE SO AS TO BE IN COMPLEMENTARY RELATION TO THE OPENING OF SAID PIERCE MEMBER OF SAID PUNCH UNIT WHEN SAID PUNCH UNIT IS POSITIONED WITHIN THE CONFINES OF SAID STEEL RULE OF SAID DIE UNIT, AND THE CAST MATERIAL WITHIN THE ENTIRE AREA BOUNDED BY THE CONFINES OF SAID STEEL RULE OF SAID DIE UNIT INTEGRALLY BONDING THE SEVERAL REACHES OF THE INNER PERIPHERY OF SAID STEEL RULE TO EACH OTHER AND TO SAID PUNCH MEMBER LOCATED WITHIN THE CONFINES OF SAID STEEL RULE, SAID CAST MATERIAL WITHIN THE INNER PERIPHERY OF SAID STEEL RULE OF SAID DIE UNIT HAVING A DEPTH CORRESPONDING GENERALLY TO THE HEIGHT OF SAID STEEL RULE MINUS A DEPTH OF ANY STRIPPER PAD TO BE DISPOSED WITHIN THE CONFINES OF SAID STEEL RULE OF SAID DIE UNIT AND MINUS ANY FURTHER DEPTH REQUIRED TO PERMIT PENETRATION OF SAID PUNCH UNIT INTO SAID DIE UNIT IN OPERATION OF THE PUNCH AND DIE UNITS AS THE COMPLEMENTARY PARTS OF A MATCHED DIE SET.
 7. A METHOD OF MAKING A DIE UNIT SUITABLE FOR USE WITH A COMPLEMENTARY PUNCH UNIT FOR BLANKING OUT A PART FROM SHEET MATERIAL COMPRISING THE STEPS OF FORMING A STEEL BLANKING RULE FOR THE DIE UNIT HAVING A CONTINUOUS CUTTING EDGE CORRESPONDING TO THE CONTOUR OF THE PART TO BE BLANKED, PROVIDING TYING MEANS IN SAID RULE, INSERTING THE COMPLEMENTARY PUNCH UNIT AT LEAST PARTIALLY INTO SAID RULE, DISPOSING A CASTING MATERIAL INTO AN AREA AROUND THE OUTSIDE OF SAID RULE TO A DEPTH GENERALLY CORRESPONDING TO THE HEIGHT OF SAID RULE THROUGHOUT ALL REACHES THEREOF TO PROVIDE A SUBSTANTIAL AREA OF CAST MATERIAL OUTSIDE OF SAID RULE, AND DISPOSING ADDITIONAL CASTING MATERIAL INTO THE SPACE ENCLOSED BY SAID RULE TO A DEPTH LESS THAN THE HEIGHT OF SAID RULE THROUGHOUT THE ENTIRE AREA BOUNDED BY SAID RULE, AND ALLOWING THE CAST MATERIAL TO SOLIDIFY BOTH INSIDE AND OUTSIDE OF SAID RULE, THEREBY TO PRODUCE THE DIE UNIT. 